Screw closure



M. B. STULL SCREW CLOSURE Sept. 5, 1967 Filed May 11, 1966 INVENTOR.Morton B. 311d! AGENT United States Patent Ofiice 3,339,773 PatentedSept. 5, 1967 This invention relates to closures for small containers,collapsible tubes and the like, and more particularly to screw-typeclosures in this category.

Objects of the invention are to provide: (1) a novel and improved screwclosure which effects a tactual indication or signal that is readilyfelt by the user just prior to the closure attaining its final, stoppedposition; (2) a closure as in (1) and which has a fast lead, i.e. isespecially fast-acting in reaching the stopped condition; (3) a threadedfast-lead closure which is especially resistant to opening under adverseconditions such as vibration, etc.; (4) a closure as above set forth,which has a positive and especially effective back-off or removalaction; (5) a closure as characterized, which provides an effective sealeven prior to attaining the fully-closed condition; (6) a closure asabove indicated, wherein the movable part is effectively and positivelyhalted upon the fully-closed condition being attained; (7) a closurewhich is especially easily and quickly removed and reapplied by theuser, providing at virtually all times an effective seal.

Further and important objects of the invention are: (a) to provide animproved threaded neck and closure combination which is free of thesestresses and strains that are normally inherent in closures wheresealing pressures are axially directed and dependent for maintenance onthe engagement of the threads of the closure; (b) to provide an improvedclosure of the type above set forth, wherein the likelihood of crossthreading, stripping or deforming the threads is eliminated; and (c) toprovide an improved closure combination wherein the closure member canbe readily started to turn towards the open position without it beingnecessary to overcome the resistance of the mechanical means that isnormally utilized to maintain the conventional axial abutment seal inaxial-pressure seal arrangements.

Other features and advantages will hereinafter appear.

In the drawings:

FIG. 1 is a view partly in axial section and partly in side elevation,of the present improved closure mounted on a collapsible tube (shown inpart only).

FIG. 2 is a view partly in axial section and partly in side elevation,of the tubular body member of the closure.

FIG. 3 is a view partly in axial section and partly in side elevation,of the screw cap member of the closure.

As shown, the improved closure comprises essentially a tubular bodymember indicated generally by the numeral 10 (see FIG. 2) and acup-shaped screw cap member designated generally by the numeral 12 (seeFIG. 3). The body member 10 is shown as being in the form of an adaptoror fitment intended to be attached to the neck of a container, such asthe collapsible tube 14 shown in FIG. 1. However, the body member 10 mayas well constitute an integral or a permanent part of the container,whether this latter is a collapsible tube, a squeeze bottle, a smallvial, or other dispensing container. In any case, the body member 10constitutes one basic part of the closure, whereas the screw cap member12 constitutes the other part of the closure.

As seen in FIG. 1, the body member 10 is press-fitted on the neck (notshown) of the collapsible tube 14, said member and neck havingcooperable detent means, such as the annular head 20 and the annulargroove 22 of the body member. Such cooperable detent means between thebody member 10 and the corresponding portion of the container form nopart of the present invention, and

accordingly further details thereof are not given herein.

The body member 10 comprises a tubular body portion 16 having at itsbottom end an annular collar 18 which fits against the conical end ofthe tube 14 in the manner shown in FIG. 1.

On the tubular body portion 16 there are disposed external screw therads24, 26 which constitute a double thread and, by virtue of this, can havea fast lead. The external screw threads 24, 26 are shown as being of Irounded section, and as being of relatively small height whereby theymay be easily wiped clean if this becomes necessary or desirable. Beyondthe screw threads 24, 26, the body portion 16 includes an orificeportion 28 of tapered or frustoconical configuration, there being adischarge passage 30 through the portions 16 and 28.

For cooperation with the external screw threads 24, 26 the screw capmember 12 has internal screw threads 32, 34 also characterized by a fastlead. The internal screw threads 32, 34 are also rounded in section andof small height, and either one or both of the members 10, 12 may beconstituted of yieldable molded plastic substance such as polyethyleneor the like. With such construction, there is a certain degree ofresilience inherent in the members 10, 12 and by virtue of this and alsothe specific illustrated configuration of the screw threads 24, 26 and32, 34 these threads constitute a somewhat impositive cap shifting meansinasmuch as it is possible to force the cap member 12 axially onto thebody member 10 with the screw threads becoming slightly distorted andforced laterally past each other. However, during the normal functioningof the closure the screw threads are not forced past each other in thismanner but instead function to axially advance the screw cap 12 onto thebody member 10 as the cap is screwed or turned in the usual manner.

In accordance with the present invention, novel detent means areprovided in conjunction with the above structure, whereby the user isprovided with a tactual indication or signal to. the effect that theclosure is fully assembled, this occurring just prior to the terminationof the screwing-on movement of the cap member 12. The said detent means,in addition to providing this tactual indication or signal, also helpsto effectively retain the screw cap member 12 in its fully closedposition under adverse conditions of use, such as vibration and thelike, in spite of the fast lead and rounded configuration of thecooperable screw threads 24, 26 and 32, 34.

The said cooperable detent means comprises a yieldable part on one ofthe members 10, 12 this being shown as in the form of a bead formationconstituted as internal ridges 38 (see FIG. 3) disposedcircumferentially in the member 12 and cooperable with an annularshoulder 40 and annular groove 42 provided on the orifice portion 28 ofthe body member 10.

During the assemblage of the cap member 12 to the body member 10, theridges 38 will ride up on the conical outer surface 44 of the orificeportion 28, thereby tending to initially constrain the said screwing-onmovement of the cap. However, as the screwing movement of the cap iscontinued, the action of the screw threads 24, 26 and 32, 34 will causethe ridges 38 to continue their travel and to be deformed, ultimatelyforcing the ridges to ride over the annular shoulder 40 of the bodymember 10, and to occupy the groove 42. As soon as the ridges 38 bypassthe annular shoulder 40, the constraining action ceases, and the turningof the cap member 12 becomes very easy for the final fraction of arevolution until the members 10, 12 attain the fully assembledcondition. This cessation of the constraining action is imparted to theuser in the form of a tactual indication or signal, indicating that thecap member 12 has now attained the proper sealing or closing position.

The invention also provides, in conjunction with the above detent meansand screw threads, additional cooperable screw elements on the members10, 12 which operate shortly after initial unscrewing movement of thecap memher from the said fully assembled condition, and which forciblyaxially shift the cap member a distance which is sufificient topositively disengage the cooperable detent means, that is, a distancesufiicient to force the ridges 38 over and past the annular shoulder 40of the orifice portion 28. Moreover, the said additional cooperablescrew elements also are arranged to constitute a positive stop means, bywhich screwing on of the cap member 12 is forcibly and positively haltedwhen the member attains the fully assembled position on the body member10.

In affecting this, the body member 10' is provided with a pair ofdiametrically opposite wedge or screw elements 48 having sloping uppersurfaces 50 and squared ends or abutting end surfaces 52. Forcooperation with the screw elements 48, the cap member 12 is providedwith a pair of internal, diametrically disposed lugs 54 having abuttingside surfaces 56 as seen in FIG. 3. With such organization, the abuttingend and side surfaces 52, 56 will be brought into engagement with eachother as the cap member 12 attains the fully assembled position on thebody member 10, thereby effectively preventing further turning movementof the cap member.

Also, upon unscrewing movement of the cap member 12, the lugs 54 will,after a slight initial interval of turning of the closure member 12,ride up on the sloped surfaces or faces 50 of the screw elements 48,causing a positive backing-off movement of the cap member 12 andforcibly shifting the ridges 38 over and past the annular shoulder 40.In consequence, dependence is not had only on the screw threads 24, 26and 32, 34 to effect removal of the cap member 12 and to force theridges 38 over the annular shoulder 40. Instead, the additional screwelements 48 will be effective at least until the ridges 38 have beenshifted past the annular shoulder 40, whereupon there no longer existsany restraint tending to prevent unscrewing of the cap member 12. Thescrew threads 24, 26 and 32, 34 will thereafter effectively complete theunscrewing of the cap member, and the fast lead which characterizes thescrew threads may be such that the attachment and removal of the capmember 12 is effected by turning the latter through not more thansubstantially onehalf of a complete revolution.

The said initial movement of the member 12 facilitates the breaking ofglue bonds, crusts and the like which sometimes form between the closureparts, and this is an important feature.

During the screwing on of the cap member 12, and after the ridges 38have been forced over and past the annular shoulder 40 of the bodymember 10, the said annular shoulder engages an internal annular sealingsurface 60 of the cap member 12, thereby to effect a seal between themembers 10 and 12. Thus, immediately upon the constraint being removednear the termination of the screwing on of the cap member 12, a seal iseffected between the shoulder 40 and the sealing surface 60 of themembers.

Also, in accordance with the invention, a second seal is effectedbetween the members 10, 12 prior to the attainment of the fullyassembled condition of the said members. This second seal comprisescooperable annular sealing elements on the members, in the form of ayieldable annular internal flange 62 in the cap member 12, whichcooperates with the top end 64 of the orifice portion 28. This isclearly illustrated in FIG. 1, which shows the fully assembled conditionof the members 10, 12. It will be seen that for such condition, theannular shoulder 40 seals against the surface 60, and the flange 62seals against the top end 64 of the body member. The engagement betweenthe flange 62 and the top end 64 occurs prior to the ultimate attainmentof the fully assembled condition, whereby a slight interference exists.The yieldability of the flange 62, however, enables the slightadditional amount of movement of the cap member 12 to be effected, untilthe stop surfaces 52, 56 are brought into engagement with each other.

I have found that with the above construction it is especially easy fora user to quickly remove the screw cap member 12 when dispensing of thecontents of the container is to be had, and just as easy for the user toreplace the screw cap and effectively restore the desired seal. Not morethan a half turn of the screw cap is required, and the user is apprisedof the fact that the seal is effected, by virtue of the tactualindication or signal being given when the screw cap approaches the finalfully assembled position. The seals which are effected involve mostlyradial forces, whereby dependence is not had on the screw threads tomaintain the seals. The detent ridges 38 effectively yiel-dably hold thescrew cap in the sealing condition regardless of vibration and otheradverse conditions of shipment, storage, etc.

The closure construction is extremely simple, and the components may bereadily economically molded by conventional molding techniques, insimple mold equipment. The cost of the components is thus held to adesirably low figure. Also, the likelihood of contamination of the screwthreads 24, 26 and 32, 34 by the product being dispensed is diminishedby locating the discharge orifice of the portion 28 at a distance fromthe body portion 16.

Variations and modifications may be made Within the scope of the claims,and portions of the improvement may be used without others.

I claim:

1. A screw closure construction comprising, in combination:

(a) a tubular body member having a discharge passage through it, andhaving means for attaching it to the mouth of a container,

(b) said body member having external screw threads surrounding thedischarge passage, and having an orifice portion beyond said screwthreads,

(0) a screw cap member adapted to be screwed onto said body member andhaving internal threads engageable with said external screw threads, and

(d) cooperable detent means on said members, in-

cluding a yieldable part on at least one member, tending to initiallyconstrain the said screwing-on of the cap,

(e) said detent means being so organized as to terminate said constraintprior to the screw cap member attaining its fully screwed-on positionrepresenting a fully-assembled condition of the members, therebyproviding to the user a tactual indication of such screwed-on positionby virtue of an easier ultimate turning action.

2. A screw closure construction as in claim 1, wherein:

(a) the cooperable detent means comprises an annular shoulder on onemember and a bead formation constituting the said yieldable part, saidformation being carried out on the other member and snapping past theshoulder before the members attain the fully assembled condition.

3. A screw closure construction as in claim 2, wherein:

(a) said annular shoulder is carried by the outside of the orificeportion of the body member, and

(b) said bead formation comprising internal ridges in the screw capmember.

4. A screw closure construction as in claim 1, wherein? (a) additionalcooperable screw elements are provided on the members, operable onlyupon an initial unscrewing movement of the cap member from the saidfully-assembled condition, to forcibly shift the cap member a distancesufiicient to disengage the said cooperable detent means,

(b) one of said members being constituted of yieldable, molded plasticsubstance,

(c) said external and internal screw threads being rounded in sectionand of relatively small height whereby they constitute an easily cleanedbut impositive cap shifting means.

5. A screw closure construction as in claim 4, wherein:

(a) said additional screw elements have a one-way screw action, and haveabutting end surfaces which engage each other and constitute a stop tohalt the cap member in the fully screwed-on position when the latter isassembled to the body member.

6. A screw closure construction as in claim 5, wherein:

(a) said screw elements comprise a pair of diametrically opposite wedgeformation having squared ends, said formations being carried at the baseof the body member.

7. A screw closure construction as in claim 1, wherein:

(a) cooperable annular sealing elements are provided on the members,said sealing elements being effectively engaged to seal the orificeportion of the body member as the detent means becomes effective duringthe assembly of the cap member to the body member.

8. A screw closure construction as in claim 7, wherein:

(a) said sealing elements comprise a yieldable annular flange on theinside of the cap member, engageable with the orifice portion of thebody member.

9. A screw closure construction as in claim 1, wherein:

(a) one of said members being constituted of yieldable, molded plasticsubstance,

(b) said external and internal screw threads being rounded in sectionand of relatively small height whereby they constitute an easily cleanedcap shifting means,

(0) said detent means and screw threads tending to hold the cap memberagainst removal axially from the body member,

(d) and cooperable sealing elements on said members, said elementsbecoming effective just prior to the members reaching thefully-assembled condition.

References Cited UNITED STATES PATENTS 7/ 19 54 McGinnis et a1. 215432/1963 Foss et al. 215-44

1. A SCREW CLOSURE CONSTRUCTION COMPRISING, IN COMBINATION: (A) ATUBULAR BODY MEMBER HAVING A DISCHARGE PASSAGE THROUGH IT, AND HAVINGMEANS FOR ATTACHING IT TO THE MOUTH OF A CONTAINER, (B) SAID BODY MEMBERHAVING EXTERNAL SCREW THREADS SURROUNDING THE DISCHARGE PASSAGE ANDHAVING AN ORIFICE PORTION BEYOND SAID SCREWED THREADS, (C) A SCREW CAPMEMBER ADAPTED TO BE SCREWED ONTO SAID BODY MEMBER AND HAVING INTERNALTHREADS ENGAGEABLE WITH SAID EXTERNAL SCREW THREADS, AND (D) COOPERABLEDETENT MEANS ON SAID MEMBERS, INCLUDING A YIELDABLE PART ON AT LEAST ONEMEMBER, TENDING TO INITIALLY CONSTRAIN THE SAID SCREWING-ON OF THE CAP,(E) SAID DETENT MEANS BEING SO ORGANIZED AS TO TERMINATE SAID CONSTRAINTPRIOR TO THE SCREW CAP MEMBER ATTAINING ITS FULLY SCREWED-ON POSITIONREPRESENT-